1. Field
Embodiments of the disclosure relate generally to the field of food service carts for airline in-flight food service and more particularly to a compartmented insulated door carrying distributed dry ice pucks with metering orifices introducing cooling flow through the door insulation for distributed cooling.
2. Background
Galley carts are used on an aircraft to store food and beverages that need to be refrigerated and/or frozen during the duration of a flight. Conventional galley carts depend on a powered heat exchanger know as a chiller to cool a housing cavity of the cart where the food products are stored. However, the heat exchanger adds weight, discharges heated gas to the environment surrounding the cart and consumes power that can be otherwise be used by the aircraft. Further, additional cabin cooling is needed to counteract the heated gas discharged from the heat exchanger. As such, at least some known galley carts use dry ice to cool the housing cavity. However, when the dry ice is placed within the cart, it cools locally and the cooling stratifies along the height of the cart. The dry ice placed within the cart cools locally and then the cooler gas settles to the bottom trays. When the cooler gas settles, the upper trays can be too warm (i.e. above 40° F.) and the lower trays are freezing (i.e. below 32° F.). To alleviate this problem, fans are added to the carts to circulate the cool gas within the cart cavity. However, the fan requires a power source. Alternatively, the dry ice can be placed in the top portion of the cart such that the upper trays are cooled locally by the dry ice and the upper and middle trays are cooled by the cool gas flowing past as it settles to the bottom trays. However, over time, the cooling further stratifies such that middle trays are warmer than upper trays and lower trays and/or the upper and middle trays are warmer than bottom trays. This problem can be addressed by fine tuning the amount of dry ice, but the amount can be difficult to determine because of the many factors impacting cooling during a flight and on the ground
It is therefore desirable to provide a galley cart with distributed cooling which overcomes the limitations of current galley carts.